Coffee shop adjusts bean grinder every day the importance of espresso grinding

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Why do cafes adjust bean grinders every day?

The coffee shop has to adjust the grinding degree every day, and some even adjust it once in a few hours, if there are strict requirements for the extraction results.

In fact, it should be adjusted every 5 hours, because the beans are changing at every moment, and even the pressure, temperature and humidity will have an impact on the extraction. And the extraction under Italian high pressure will expand the influence and know how to adjust, which is the self-cultivation of a good barista.

Why do you need to adjust the grinding?

Only 30% of roasted coffee beans are soluble.

In general, the best extraction rate of espresso is about 18-22%.

So in order to keep the extraction rate of Italian concentration between 18 and 22%, we need to adjust the degree of grinding.

To control the speed and time of hot water passing through coffee powder, and finally achieve the purpose of controlling the extraction rate.

Every small change in the bean grinder will have a great impact on the overall quality of the coffee.

Therefore, as a barista, you should re-measure and adjust the bean grinder every day to ensure the perfect quality of the coffee.

The significance of adjusting bean grinder

The humidity and storage time of coffee beans are constantly changing, and the wear degree of bean grinder blades also changes with time.

So baristas should adjust the bean grinder regularly to ensure that the ground coffee powder remains perfect.

When the coffee bean enters the grinder, the blade in the grinder will crush the coffee bean into powder.

The smaller the distance between the blade and the blade, the smaller the coffee beans will be ground into smaller particles.

The finer the grinding particles are, the tighter they are, and the more difficult it is for the water to pass through, thus greatly prolonging the extraction time.

On the contrary, if the distance between the blades increases, the ground particles will become rougher, the flow of water will be easier to pass through, and the extraction time will be faster.

To take a simple example, like stones and fine sand, water flows through stones much faster than fine sand.

Because there is more space between the stones for the water to flow through quickly. Therefore, the correct grinding is very important, and the particle size directly affects the quality of the extraction.